Organic lithium-iodine battery based on two-electron transfer mechanism, manufacturing method and application thereof

Abstract

The application provides an organic lithium-iodine battery based on a two-electron transfer mechanism and a manufacturing method and application thereof. The organic lithium-iodine battery comprises a positive electrode, a negative electrode and an organic electrolyte. The positive electrode active material used by the positive electrode comprises iodide and / or bromide, and the organic electrolyte comprises an organic solvent containing a chlorine-containing additive. The organic lithium-iodine battery uses iodide as the positive electrode active material, thereby avoiding the instability and safety hazards existing in the current I2 positive electrode. The organic solvent containing the chlorine-containing additive is used as the organic electrolyte, and excellent electrochemical performance is provided through a two-electron conversion mode. Compared with a traditional lithium-iodine battery, the organic lithium-iodine battery has higher capacity, energy density and higher output voltage. In addition, the organic lithium-iodine battery has excellent low-temperature insensitivity. At-25 DEG C, the battery realizes 2500 cycles at the cost of 20% capacity decay, and can still work stably at a low temperature of-30 DEG C.

Description

Technical Field

[0001] This invention relates to an organic lithium-iodine battery based on a two-electron transfer mechanism, its manufacturing method and application, and belongs to the field of organic lithium-iodine battery technology. Background Technology

[0002] High discharge capacity and high output voltage are the two major goals pursued in battery development. Unfortunately, they cannot usually be achieved simultaneously. For the most maturely researched rocker-type or intercalated lithium-ion batteries, their high voltage output platform is outstanding, but their capacity is often unsatisfactory. For example, the output voltage of LiCoMnO4 cathode is as high as 5.3V, but its capacity is only 150mAh g / g. -1 Low discharge capacity is typically caused by ineffective ion insertion and limited electron exchange, leading to the collapse of the cathode active material structure. One promising alternative is conversion batteries based on conversion reaction mechanisms, including lithium-iodine, bromine, sulfur, selenium, chlorine, or oxygen systems. With abundant valence state transitions and significant electron transfer, these systems often exhibit high discharge capacity, but their discharge voltage is typically undesirable (e.g., 2.4V for lithium-sulfur batteries, 3.4V for lithium-bromine batteries, and 2.9V for lithium-iodine batteries). Furthermore, the shuttle effect is particularly severe in these systems. Increasing the discharge voltage of these conversion batteries is an effective way to achieve high energy density, which requires the introduction of novel redox mechanisms.

[0003] Iodine and bromine naturally possess diverse valence states, thus holding promise for achieving higher output voltages by activating novel redox reactions. Currently, the power supply mechanism of lithium-iodine / bromine batteries utilizes X... - / X 0 (X: iodine or bromine) A reversible conversion between redox pairs is achieved with the transfer of a single electron. It is worth noting that elemental bromine electrodes are based on a liquid-liquid conversion mode, and their stability is considered far inferior to that of elemental iodine electrodes. The intrinsic liquid properties and severe corrosiveness of elemental bromine make it difficult to apply to portable energy storage devices; it is typically used in flow-type energy storage equipment. Organic lithium-iodine batteries utilize the controversial I... - / I3 - Or I - The reversible transition of the I₂ redox pair enables charge transfer, but its theoretical discharge capacity is only 211 mAh g⁻¹. -1 The output voltage is typically below 2.9V. However, the high-valence I... + Cations are thermodynamically unstable in electrolytes and almost irreversibly convertible. Previous studies involving iodate cations have not been successful in organic systems. Ideally, once I... + The cation conversion is activated and stabilized, reversible I... 0 / I+ Redox will trigger a new conversion plateau, whose conversion potential is higher than I. - / I 0 The redox couple is approximately 0.5V higher. Furthermore, the two-electron transfer mode is expected to double the theoretical capacity to 422 mAh g. -1 More importantly, energy density will achieve a significant increase of over 200% compared to the original value (e.g., Figure 1a and Figure 1b (As shown).

[0004] Another drawback of lithium-iodine batteries is related to the thermodynamic instability of elemental iodine. Elemental iodine spontaneously sublimates and is difficult to store for extended periods, even at room temperature. Furthermore, lithium-iodine batteries exhibit slow kinetics and poor reversibility under harsh low-temperature conditions, leading to rapid capacity decay and even battery failure, thus limiting their application scenarios. Current research largely focuses on developing porous hosts to accommodate elemental iodine and reaction products; however, host-guest interactions are primarily limited to physical adsorption, resulting in limited strength and making it difficult to effectively suppress the shuttle behavior of polyiodides during cycling.

[0005] Therefore, in response to the problems of low capacity, low redox potential, poor long-cycle performance, and slow kinetics that are easily identified in organic lithium-iodine (Li-I) batteries due to the single-electron transfer mechanism and shuttle effect, which make them inferior to other similar conversion batteries, providing a novel organic lithium-iodine battery based on a two-electron transfer mechanism, its fabrication method, and its application has become an urgent technical problem to be solved in this field. Summary of the Invention

[0006] To address the aforementioned drawbacks and shortcomings, one objective of this invention is to provide an organic lithium-iodine battery.

[0007] Another object of the present invention is to provide a method for manufacturing the above-described organic lithium-iodine battery.

[0008] Another object of the present invention is to provide the application of the above-described organic lithium-iodine battery in automobiles, computers, or robots. In this invention, the newly activated I... - / I + The redox reaction, which generates and facilitates two-electron transfer, significantly enhances the electrochemical performance of the organic lithium-iodine battery, far exceeding that of traditional batteries with I₂. - / I3 - / I 0The lithium-iodine battery provided by this invention is a high-performance organic lithium-iodine battery. It has excellent electrochemical properties such as capacity, energy density, high output voltage and long-term cycle stability, as well as low-temperature insensitivity, safety, high efficiency and reversibility. This organic lithium-iodine battery shows good energy storage prospects in high-energy-density devices and shows great competitiveness in the future energy market.

[0009] To achieve the above objectives, in one aspect, the present invention provides an organic lithium-iodine battery, wherein the organic lithium-iodine battery comprises:

[0010] positive electrode;

[0011] negative electrode;

[0012] And organic electrolytes;

[0013] The positive electrode active material used in the positive electrode includes iodides and / or bromides, and the organic electrolyte includes an organic solvent containing chlorine-containing additives.

[0014] In one specific embodiment of the organic lithium-iodine battery described above in this invention, the negative electrode comprises lithium foil or graphite.

[0015] In one specific embodiment of the organic lithium-iodine battery described above in this invention, the positive electrode comprises a current collector, a positive electrode active material, a conductive agent, and one or more binders.

[0016] As a specific embodiment of the organic lithium-iodine battery described above in this invention, the amount of positive electrode active material is 1-99 wt%, the amount of conductive agent is 0.1-90 wt%, and the amount of adhesive is 0.01-20 wt%, with the total weight of positive electrode active material, conductive agent, and adhesive being 100%.

[0017] In this invention, the specific substances of the conductive agent and binder are not specified, and they can be reasonably selected according to actual operational needs. As a specific embodiment of the organic lithium-iodine battery described above, the conductive agent is conductive particles.

[0018] In one specific embodiment of the organic lithium-iodine battery described above in this invention, the iodide used as the positive electrode active material includes one or more of methyl ammonium iodide, trimethylammonium iodide, tetrabutylammonium iodide, and tetrabutylammonium triiodide. These iodides used in this invention can provide active iodine and all possess thermal stability, thus replacing traditional I2.

[0019] In one specific embodiment of the organic lithium-iodine battery described above in this invention, the bromide used as the positive electrode active material includes tetramethylammonium bromide and / or tetramethylammonium tribromide.

[0020] In one specific embodiment of the organic lithium-iodine battery described above in this invention, the current collector includes one of carbon cloth, carbon paper, aluminum foil, and nickel foam. In some embodiments of this invention, the carbon paper may be, for example, carbon nanotube paper.

[0021] In one specific embodiment of the organic lithium-iodine battery described above in this invention, the concentration range of the chlorine-containing additive is 0.01-10M based on the total volume of the organic solvent.

[0022] As a specific embodiment of the organic lithium-iodine battery described above in this invention, the chlorine-containing additive includes one or more of LiCl, NH4Cl, CaCl2, CsCl, FeCl2, MgCl2, KCl, NaCl, AgCl, and ZnCl2.

[0023] In one specific embodiment of the organic lithium-iodine battery described above in this invention, the organic solvent containing chlorine-containing additives further comprises a lithium salt electrolyte.

[0024] In one specific embodiment of the organic lithium-iodine battery described above, the concentration of the lithium salt electrolyte ranges from 0.01 to 10 M, based on the total volume of the organic solvent.

[0025] As a specific embodiment of the organic lithium-iodine battery described above in this invention, the lithium salt electrolyte includes any one of LiTFSI, LiOTf, LiPF6, LiClO4, LiBF4, LiAsF6, LiCF3SO3, LiN(CF3SO2)2, LiBOB, LiDFOB, LiFSI, LiNO3, and LiCl.

[0026] As a specific embodiment of the organic lithium-iodine battery described above in this invention, the organic solvent includes one or more of acetonitrile, dimethyl sulfoxide, tetrahydrofuran, propylene carbonate, ethyl methyl carbonate, ethylene carbonate, dimethyl carbonate, vinylene carbonate, propylene sulfite, methyl propionate, fluoroethylene carbonate, dimethoxyethane, and dioxolane.

[0027] On the other hand, the present invention also provides a method for manufacturing the above-described organic lithium-iodine battery, wherein the manufacturing method includes:

[0028] The production of the positive electrode:

[0029] The positive electrode active material, conductive agent, and binder are mixed evenly in a solvent to obtain a slurry. The slurry is then coated onto a current collector and dried to obtain the positive electrode.

[0030] Assembly of organic lithium-iodine batteries:

[0031] The positive electrode, negative electrode, and organic electrolyte are assembled to obtain an organic lithium-iodine battery.

[0032] The battery assembly process is a conventional technical method in this field and can be carried out reasonably according to actual operational needs.

[0033] Furthermore, this invention also provides applications of the aforementioned organic lithium-iodine batteries in automobiles, computers, or robots. The organic lithium-iodine battery provided by this invention is highly competitive in the fields of large-scale storage and power supply for electronic devices over a wide temperature range.

[0034] Compared with the prior art, the beneficial technical effects achieved by the organic lithium-iodine battery provided by the present invention include:

[0035] (1) The organic lithium-iodine battery provided by the present invention has low cost and is simple to manufacture.

[0036] (2) The organic lithium-iodine battery provided by the present invention uses iodide as the positive electrode active material, which avoids the instability and safety hazards that exist in the current use of I2 as the positive electrode.

[0037] (3) The organic lithium-iodine battery provided by this invention uses an organic solvent containing chlorine-containing additives as an organic electrolyte, providing excellent electrochemical performance through a dual-electron conversion mode. Compared with traditional lithium-iodine batteries, it has higher capacity, energy density, and higher output voltage. Specifically, in the embodiments of this invention, a safe and stable halide (methylammonium iodide) is developed as an electrochemically active iodine source to replace elemental iodine, thereby achieving chemical adsorption of iodine by the host rather than just physical adsorption. Simultaneously, the introduction of chloride ions (0.1M) as an additive into the commercial electrolyte can fully activate and stabilize the reversible I-phase of the halide (methylammonium iodide) cathode. 0 / I + Redox reactions occur. Therefore, the ammonium methyl iodide cathode paired with the lithium metal anode exhibits two distinct discharge plateaus, located at 2.91V and 3.42V, respectively. Based on this, the new 3.42V high-voltage plateau in the organic lithium-iodine battery doubles its total discharge capacity, reaching 408 mAh g⁻¹. -1 It exhibits rapid redox kinetics and superior long-term cycling stability. More importantly, its energy density can be increased to an astonishing 1324 Wh / kg. -1 This achieves 238% of the efficiency of traditional lithium-iodine batteries based on a single-electron conversion reaction mechanism, outperforming all currently reported organometallic-iodine batteries (such as lithium-iodine, potassium-iodine, sodium-iodine, and magnesium-iodine) and most rocking-chair lithium-oxide battery systems. Furthermore, the activated voltage plateau region significantly improves the effective energy output in the high-voltage region.

[0038] (4) The organic lithium-iodine battery provided by the present invention uses an organic solvent containing chlorine additives, which gives it excellent low temperature insensitivity. At -25°C, the battery achieves 2,500 cycles at the cost of 20% capacity decay, and can still work stably at low temperature conditions of -30°C. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1a This is a schematic diagram of the iodine conversion mechanism in lithium-iodine batteries.

[0041] Figure 1b For lithium-iodine batteries and Figure 1a The diagram shows the electrochemical performance improvement corresponding to the iodine conversion mechanism.

[0042] Figure 2a This is a schematic diagram of the crystal structure of MAI in Test Example 1 of the present invention.

[0043] Figure 2b This is the SEM image of MAI in Test Example 1 of the present invention.

[0044] Figure 2c The Raman spectrum of MAI is shown in Test Example 1 of this invention.

[0045] Figure 2d This is the full XPS spectrum of MAI in Test Example 1 of this invention.

[0046] Figure 2e This is the high-resolution I3d XPS spectrum of MAI in Test Example 1 of the present invention.

[0047] Figure 2f This is a graph showing the weight changes of elemental iodine and MAI material at 60°C in Test Example 1 of this invention.

[0048] Figure 2g The graph shows the thermal stability of elemental iodine at 60°C in Test Example 1 of this invention.

[0049] Figure 2h This is the EDX mapping result of elemental iodine in Test Example 1 of the present invention.

[0050] Figure 2i This is the EDX mapping result of element carbon in Test Example 1 of the present invention.

[0051] Figure 2j This is the EDX spectrum of the MAI material in Test Example 1 of the present invention.

[0052] Figure 3 This is a comparison chart of the loading of iodine, the active material, in MAI and other composite iodine cathode materials in Test Example 2 of the present invention.

[0053] Figure 4a In Test Example 3 of this invention, the MAI / / LDL / / Li battery and the MAI / / Cl-LDL / / Li battery were tested at 0.5 mV s. -1 CV curve at sweep speed.

[0054] Figure 4b The CV curves of the MAI / / Cl-LDL / / Li battery at different scan rates are shown in Test Example 3 of this invention.

[0055] Figure 4c The b values ​​of the four redox peaks of the MAI / / Cl-LDL / / Li battery were calculated according to formula (1) in test example 3 of the present invention.

[0056] Figure 4dThis is a CV curve of the MAI / / Cl-LDL / / Li battery at different high scan rates in Test Example 3 of this invention.

[0057] Figure 4e The redox potentials of the MAI / / Cl-LDL / / Li battery at different scan rates in Test Example 3 of this invention.

[0058] Figure 4f In Test Example 3 of this invention, the MAI / / LDL / / Li battery and the MAI / / Cl-LDL / / Li battery were tested at 0.5 A g. -1 Charge-discharge curves at current density.

[0059] Figure 4g The figure shows the GITT curve of the MAI / / Cl-LDL / / Li battery in Test Example 3 of this invention. The inset shows the corresponding ion diffusion coefficient.

[0060] Figure 4h for Figure 4g The corresponding magnified GITT curve and the measured overpotential of region I.

[0061] Figure 4i for Figure 4g The corresponding magnified GITT curve and the measured overpotential of region II.

[0062] Figure 4j For the basis of Figure 4g The image shows an amplified curve of the ion diffusion coefficient calculated from the GITT curve.

[0063] Figure 5a In Test Example 4 of this invention, the MAI / / Cl-LDL / / Li battery was tested at a range of 0.5 to 5 A g. -1 Rate performance of the battery under a wide range of current densities.

[0064] Figure 5b For example Figure 5a The charge-discharge curves corresponding to the rate performance are shown.

[0065] Figure 5c In Test Example 4 of this invention, the MAI / / Cl-LDL / / Li battery was tested at 0.5 A g. -1 Long-cycle performance at current density.

[0066] Figure 5d In Test Example 4 of this invention, the MAI / / Cl-LDL / / Li battery was tested at 2.0 A g. -1 Long-cycle performance at current density.

[0067] Figure 5eIn Test Example 4 of this invention, the MAI / / Cl-LDL / / Li battery was tested at 0.5 A g. -1 Discharge curves at current density. The area covered by the vertical dashed lines represents brand new I. 0 / I + The contribution of redox reactions.

[0068] Figure 5f This is a schematic diagram showing the enhancement of energy density in the voltage plateau region of the MAI / / Cl-LDL / / Li battery at different rates in Test Example 4 of the present invention.

[0069] Figure 5g This is a schematic diagram comparing the electrochemical performance (discharge capacity, average voltage, and energy density) of the MAI / / Cl-LDL / / Li battery with existing organometallic-iodine batteries (the metals include lithium ions, potassium ions, sodium ions, and magnesium ions) and intercalated lithium-oxide batteries in Test Example 4 of this invention.

[0070] Figure 6a This is the Raman spectrum of the MAI cathode under different selected states of charge (SOC) in Test Example 5 of the present invention.

[0071] Figure 6b The UV-vis spectra of MAI electrodes under different selected charging states are shown in Test Example 5 of this invention.

[0072] Figure 6c This is a SEM image of the MAI electrode after it has been charged to 3.0V in Test Example 5 of the present invention.

[0073] Figure 6d This is a SEM image of the MAI electrode after it has been charged to 3.85V in Test Example 5 of the present invention.

[0074] Figure 6e This is the EDX mapping result of the I element in the MAI electrode at 3.85V in Test Example 5 of the present invention.

[0075] Figure 6f This is the EDX mapping result of the Cl element in the MAI electrode at 3.85V in Test Example 5 of the present invention.

[0076] Figure 7a In Test Example 6 of this invention, for the MAI / / Cl-LDL / / Li battery, the calculated Cl content / absence was... - Cohesive energy of redox products in ionic phases. The inset represents the optimized molecular structure of redox products in different states.

[0077] Figure 7b This is the electronic positioning function of the redox product in Test Example 6 of the present invention.

[0078] Figure 7c In Test Example 6 of this invention, the atomic charges of I and Cl in the I-Cl2 and I-Cl redox products were calculated.

[0079] Figure 7d This is a schematic diagram of a possible conversion process in Test Example 6 of the present invention.

[0080] Figure 7e This is a summary and comparison of the cohesive energy of redox intermediates in different redox routes in Test Example 6 of this invention.

[0081] Figure 8a The diagram shows the discharge capacity and cycle performance of the MAI / / Cl-LDL / / Li battery in different temperature ranges in Test Example 7 of this invention.

[0082] Figure 8b The GCD curves of the MAI / / Cl-LDL / / Li battery in Test Example 7 of this invention are shown at temperatures of 25°C, -25°C, and -30°C.

[0083] Figure 8c In Test Example 7 of this invention, based on as follows Figure 8b The dQ and dV calculated from the GCD curve shown are -1 Line graph.

[0084] Figure 8d The graph shows the long-cycle performance results of the MAI / / Cl-LDL / / Li battery at -25°C in Test Example 7 of this invention.

[0085] Figure 8e In Test Example 7 of this invention, two MAI / / Cl-LDL / / Li batteries connected in series illuminated a large-size (160mm×100mm) electroluminescent panel / cold light plate at a low temperature of -25℃.

[0086] Figure 8f The EIS spectra of the MAI / / Cl-LDL / / Li battery in Test Example 7 of this invention are obtained at different temperatures from 25°C to -30°C.

[0087] Figure 8g The Rct, Ro values, and capacity retention data of the MAI / / Cl-LDL / / Li battery were calculated at different temperatures from 25°C to -30°C in Test Example 7 of this invention.

[0088] Figure 8h In Test Example 7 of this invention, the MAI / / Cl-LDL / / Li battery was tested at -25°C and 1.0 A g. -1 GCD curve under cyclic conditions. Detailed Implementation

[0089] It should be noted that the term "comprising" and any variations thereof in the specification, claims, and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.

[0090] The "range" disclosed in this invention is given in the form of a lower limit and an upper limit. It can be one or more lower limits and one or more upper limits, respectively. A given range is defined by selecting a lower limit and an upper limit. The selected lower and upper limits define the boundaries of the particular range. All ranges defined in this way are composable, meaning that any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for specific parameters, it is also expected that ranges of 60-110 and 80-120 are also expected. Furthermore, if the listed minimum range values ​​are 1 and 2, and the listed maximum range values ​​are 3, 4, and 5, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5.

[0091] In this invention, unless otherwise specified, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this invention, and "0-5" is simply a shortened representation of these numerical combinations.

[0092] In this invention, unless otherwise specified, all embodiments and preferred embodiments mentioned in this invention can be combined with each other to form new technical solutions.

[0093] In this invention, unless otherwise specified, all technical features and preferred features mentioned in this invention can be combined with each other to form new technical solutions.

[0094] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments described below are some, but not all, embodiments of this invention, and are only used to illustrate the invention, and should not be considered as limiting the scope of the invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0095] The pharmaceuticals, battery materials, and components used in the embodiments of the present invention are shown below. These pharmaceuticals, battery materials, and components are all commercially available conventional substances that are purchased and used directly without any post-processing.

[0096] Ammonium methyl iodide (MAI, 99%, Aladdin), bis(trifluoromethane)sulfonimide lithium salt (LiTFSI, 99%, Aladdin), lithium nitrate (LiNO3, 99%, Aladdin), lithium chloride (LiCl, 99%, Aladdin), dimethoxyethane (DME, 99%, Aladdin), dioxolane (DOL, 99%, Aladdin), poly(vinylidene fluoride) 470 (PVDF, average Mw ~400000, Aladdin), N-methyl-2-pyrrolidone (NMP, 99%, Aladdin), Ketjenblack (ECP-600JD, Lion Corporation).

[0097] Example 1

[0098] This embodiment provides an organic lithium-iodine battery, which is manufactured according to a method including the following specific steps:

[0099] The production of the positive electrode:

[0100] The above-mentioned MAI powder, Ketjen Black, and PVDF were mixed in N-methylpyrrolidone solvent at a mass ratio of 8:1:1, and then stirred vigorously for 0.5 h. The resulting slurry was then coated onto flexible carbon cloth (380 μm thick) and dried in a vacuum oven at 70 °C for 24 h to obtain a flexible positive electrode. The areal mass loading of the positive electrode was controlled at approximately 3 mg cm⁻¹. -2 ;

[0101] Preparation of organic solvents (organic electrolytes) containing chlorine-containing additives:

[0102] The organic electrolyte is prepared by dissolving 1M LiTFSI, 0.2M LiNO3 and 0.1M LiCl in a solvent mixture consisting of DOL and DME in a volume ratio of 1:1, and in a glove box filled with Ar atmosphere. The organic electrolyte is denoted as Cl-LDL (the solvent mixture consisting of DOL and DME contains 1M LiTFSI + 0.2M LiNO3 + 0.1M LiCl).

[0103] Assembly of organic lithium-iodine batteries:

[0104] A CR2032 button-type organic lithium-iodine battery, denoted as MAI / / Cl-LDL / / Li battery, was assembled using a 300 μm thick lithium metal sheet (lithium foil) as the negative electrode, a flexible positive electrode (a disk with a diameter of approximately 12 mm) prepared above as the positive electrode, a commercially available Celgard 2400 membrane with a thickness of 18 μm, and an organic solvent containing LiCl prepared above as the organic electrolyte. The absolute MAI content in the MAI / / Cl-LDL / / Li battery is estimated to be approximately 2.7 mg.

[0105] Example 2

[0106] This embodiment provides an organic lithium-iodine battery, which is manufactured according to a method including the following specific steps:

[0107] The production of the positive electrode:

[0108] Trimethylammonium iodide powder, Ketjen black, and PVDF were mixed in N-methylpyrrolidone solvent at a mass ratio of 8:1:1, and then vigorously stirred for 0.5 h. The resulting slurry was then coated onto flexible carbon cloth (380 μm thick) and dried in a vacuum oven at 70 °C for 24 h to obtain a flexible positive electrode. The areal mass loading of the positive electrode was controlled at approximately 3 mg / cm². -2 ;

[0109] Preparation of organic solvents (organic electrolytes) containing chlorine-containing additives:

[0110] The organic electrolyte is prepared by dissolving 1M LiTFSI, 0.2M LiNO3 and 0.1M LiCl in a solvent mixture consisting of DOL and DME in a volume ratio of 1:1, and in a glove box filled with Ar atmosphere. The organic electrolyte is denoted as Cl-LDL (the solvent mixture consisting of DOL and DME contains 1M LiTFSI + 0.2M LiNO3 + 0.1M LiCl).

[0111] Assembly of organic lithium-iodine batteries:

[0112] A CR2032 button-type organic lithium-iodine battery, denoted as MAI / / Cl-LDL / / Li battery, was assembled using a 300 μm thick lithium metal sheet (lithium foil) as the negative electrode, a flexible positive electrode (a disk with a diameter of approximately 12 mm) prepared above as the positive electrode, a commercially available Celgard 2400 membrane with a thickness of 18 μm, and an organic solvent containing LiCl prepared above as the organic electrolyte. The absolute MAI content in the MAI / / Cl-LDL / / Li battery is estimated to be approximately 2.7 mg.

[0113] Comparative Example 1

[0114] This comparative example provides an organic lithium-iodine battery, which is prepared according to a method including the following specific steps:

[0115] The production of the positive electrode:

[0116] The above-mentioned MAI powder, Ketjen Black, and PVDF were mixed in N-methylpyrrolidone solvent at a mass ratio of 8:1:1, and then stirred vigorously for 0.5 h. The resulting slurry was then coated onto flexible carbon cloth (380 μm) and dried in a vacuum oven at 70 °C for 24 h to obtain a flexible positive electrode. The areal mass loading of the positive electrode was controlled at approximately 3 mg / cm². -2 ;

[0117] Preparation of organic electrolyte:

[0118] The organic electrolyte is prepared by dissolving 1M LiTFSI and 0.2M LiNO3 in a solvent mixture consisting of DOL and DME in a volume ratio of 1:1, and in a glove box filled with Ar atmosphere. The organic electrolyte is denoted as LDL (the solvent mixture consisting of DOL and DME contains 1M LiTFSI + 0.2M LiNO3).

[0119] Assembly of organic lithium-iodine batteries:

[0120] A CR2032 button-type organic lithium-iodine battery, denoted as MAI / / LDL / / Li battery, was assembled using a 300 μm thick lithium metal sheet (lithium foil) as the negative electrode, a flexible positive electrode (a disk with a diameter of approximately 12 mm) prepared above as the positive electrode, and a commercially available Celgard 2400 with a thickness of 18 μm as the separator, and using the organic electrolyte described above. The absolute MAI content in the MAI / / LDL / / Li battery is estimated to be approximately 2.7 mg.

[0121] Test Example 1

[0122] In this test case, MAI powder was analyzed using XRD, SEM, Raman spectroscopy, high-resolution I3d XPS, thermogravimetric analysis, and EDX. XRD analysis used a Bruker D2 Avance X-ray diffractometer to record the XRD pattern; SEM analysis used a Hitachi SU4800 cold field emission scanning electron microscope to characterize the morphology and microstructure of the material; XPS analysis used an ESCALAB 250 X-ray photoelectron spectroscopy system to analyze the surface composition of the material; and Raman spectroscopy was performed using a Renishaw 2000 microscope, and Raman spectra were collected using this instrument.

[0123] The crystal structure diagram, SEM image, Raman spectrum, high-resolution I3d XPS spectrum of MAI, and the weight change diagram of elemental iodine and MAI material at 60℃ are shown below. Figures 2a-2e As shown. From Figure 2a As can be seen from this, in methylammonium iodide, the iodide ion I... - It bonds to nitrogen via ionic bonds. For example... Figure 2b The scanning electron microscope (SEM) image shown reveals a pitted surface on the MAI crystal. The corresponding X-ray energy spectrum (e.g., ...) Figures 2h-2j The study revealed that iodine (I) and carbon (C) were evenly distributed within the sample, with a mass ratio of approximately 79:21.

[0124] from Figure 2c The Raman spectrum shown shows that at 110 cm⁻¹ -1 The main peak at that location is related to the vibration of the Ni bond.

[0125] Furthermore, X-ray photoelectron spectroscopy (XPS) was used to analyze the detailed valence states of iodine (I). For example... Figure 2d The XPS full spectrum shown detected three elements: C, N, and I. In, as... Figure 2e In the high-resolution I3d XPS spectrum shown, two distinct peaks were identified at 619 eV and 630 eV, respectively, corresponding to the NI bond, where I exhibits a negative monovalent.

[0126] It is also worth noting that MAI halides possess excellent thermal stability and can serve as a reactive substance to replace traditional elemental iodine. For example... Figure 2f and Figure 2gThe weight changes of elemental iodine and MAI material at 60°C and the thermal stability results of elemental iodine at 60°C are shown in the figure. Using elemental iodine as a reference, this embodiment tested the long-term stability of the MAI material. The entire test was conducted in a nitrogen-filled glove box at 60°C. As expected, elemental iodine completely evaporated within 2 hours, while the MAI material maintained a stable weight for a considerable period. Figure 2f The results show that the MAI material lost only 1.8 wt.% of its weight within 480 h, which is most likely due to the evaporation of adsorbed water.

[0127] Test Example 2

[0128] The mass fraction of active iodine in the cathode (the mass of iodine alone) is an important indicator of cathode availability. Therefore, this test case examines the loading of iodine, the active material, in MAI and other composite iodine cathode materials. The resulting comparisons are as follows: Figure 3 As shown, from Figure 3 As can be seen from the example, in the flexible positive electrode provided in Example 1, the loading of active material iodine (iodine element) reaches a satisfactory 63 wt.%, which is calculated by the weight of active material iodine element in the electrode / total weight of the electrode × 100% (iodine in MAI is 79 wt.%, and MAI in the entire flexible positive electrode is 80 wt.%). This value is higher than the loading of active material iodine in most existing composite electrodes, such as porous carbon-iodine, metal-organic framework-iodine, and polyvinylpyrrolidone-iodine.

[0129] Test Example 3

[0130] This test case investigated the electrochemical performance of MAI / / Cl-LDL / / Li and MAI / / LDL / / Li batteries. During the electrochemical performance evaluation, the electrolyte and lithium anode were overused to ensure complete electrochemical conversion of the cathode. Specifically, constant current charge / discharge measurements were performed using a LAND CT2001A battery testing equipment. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) data were recorded using a CHI 760D multichannel electrochemical workstation. Furthermore, all capacity and energy density values ​​in this test case were calculated based on the pure iodine content in the MAI cathode.

[0131] Figure 4a The MAI / / LDL / / Li and MAI / / Cl-LDL / / Li cells were shown at 0.5 mV s. -1 Cyclic voltammetry (CV) curves at different scan rates. From Figure 4a As can be seen, the MAI / / LDL / / Li battery exhibits a pair of typical redox peaks at voltages of 3.00 / 2.96V, corresponding to I...- / I3 - Redox pairs exhibit reversible transitions. In stark contrast, two distinct redox peak pairs can be identified in the MAI / / Cl-LDL / / Li battery. Besides the aforementioned 3.00 / 2.96 V peaks, another redox peak pair exists at 3.45 / 3.34 V, indicating the activation of a new reversible chemistry. Notably, the 0.4-0.5 V voltage difference between the two reduction peaks suggests that the new redox pair may originate from I₂. 0 / I + Redox pairs. The narrow full width at half maximum (FWHM) of the new peak and the strong current response indicate that the reaction has excellent kinetics and reversibility.

[0132] To elucidate the kinetic evolution of MAI / / Cl-LDL / / Li batteries with a two-stage redox process, this test case investigated the MAI / / Cl-LDL / / Li battery in the range of 0.1–1.0 mV s. -1 CV curves for the sweep speed range, such as Figure 4b As shown, from Figure 4b As can be seen, two pairs of similar redox peaks can be identified in the CV curves at all rates, indicating that the reversible conversion is efficient and stable. Benefiting from the efficient conversion kinetics, the redox potential only decreases from 0.1 mV / s. -1 The V offset at the sweep rate was 2.97 / 3.36V, which shifted to 1.0mV / s. -1 At 2.95 / 3.31V, the voltage hysteresis is only 0.02V and 0.05V.

[0133] To elucidate the charge storage mode of the MAI / / Cl-LDL / / Li battery, this test case separates the response current based on the following formula (1) and further calculates the b values ​​of the four redox peaks:

[0134] i = av b Formula (1);

[0135] In formula (1), i and v represent the peak response current and the applied scan rate, respectively. Generally, when b equals 1, the reaction is capacitively limited. For diffusion-controlled processes, b is close to 0.5. For example... Figure 4c As shown, the b-values ​​for the two pairs of redox peaks were calculated to be 0.60 / 0.58 and 0.63 / 0.57, respectively. Therefore, the new I... 0 / I + Redox pairs are considered to be controlled by both capacitance and diffusion processes, with the latter being dominant.

[0136] Between 2 and 10 mV s -1 At high scan rates, the entire I - / I+ The transformation preserved clear two-level characteristics, such as Figure 4d As shown. As a supplementary analysis, this test case extracted and compared the changes in reduction potential of two individual reactions with scan rate, as shown. Figure 4e As shown. It is worth noting that when the scan rate increases by 100 times, I... 0 / I + The redox couple exhibited a voltage hysteresis of only 0.24 V, indicating its excellent conversion kinetics. Furthermore, the electrochemical differences between the two cells were also evident in the galvanostatic measurements. Figure 4f The value at 0.5A g is given. -1 The galvanostatic charge / discharge (GCD) curves of the two batteries at current densities, from... Figure 4f As can be seen from this, the MAI / / LDL / / Li battery only has I - / I 0 The conversion resulted in a discharge plateau at a potential of 2.91V, while based on I... - / I + The redox MAI / / Cl-LDL / / Li battery exhibits two distinct discharge plateaus at 2.91 V and 3.42 V, consistent with the aforementioned CV results. Furthermore, the discharge capacity of the MAI / / Cl-LDL / / Li battery is significantly higher than that of the MAI / / LDL / / Li battery, at 408 mAh g⁻¹. -1 and 197mAh g -1 Please note that the increased capacity in the former stems entirely from the emergence of the 3.42V platform region, i.e., the activated I... 0 / I + Conversion.

[0137] Furthermore, this test case was characterized using galvanostatic intermittent titration (GITT) using conventional methods in the art to clarify the superior kinetics of the battery in terms of ion diffusion. Figure 4g The GITT curves (voltage vs. time) clearly reveal the two-stage discharge mode of the entire redox process. The two distinct discharge plateaus observed in Region I and Region II both exhibit low overpotentials of 17 mV and 30 mV (e.g., ...). Figure 4h and Figure 4i This result confirms their low equilibrium potential and fast ion diffusion kinetics. Based on the GITT curves, the corresponding ion diffusion coefficients were further calculated in this test case. Figure 4g Illustrations and Figure 4j As shown, the ion diffusion coefficient of this battery does not fluctuate significantly in region I (2.8-3.0V) and region II (3.3-3.5V), unlike intercalated electrodes.

[0138] Test Example 4

[0139] Following the unveiling of a novel redox mechanism for the MAI / / Cl-LDL / / Li battery, this test case evaluates the battery's electrochemical performance in galvanostatic mode. During the electrochemical performance assessment, the electrolyte and lithium anode were overused to ensure complete electrochemical conversion of the cathode. Specifically, galvanostatic charge / discharge measurements were performed using a LAND CT2001A battery testing equipment. Furthermore, all capacity and energy density measurements in this test case are calculated based on the pure iodine content in the MAI cathode.

[0140] Figure 5a It showed values ​​from 0.5 to 5 A g. -1 The rate performance of the battery across a wide range of current densities, from Figure 5a It can be seen from this that at 0.5A g -1 At that time, the battery discharge capacity reached 408mAh g. -1 Approaching the theoretical upper limit of the two-electron transfer mechanism (422 mAh g) -1 As the current density increased, the discharge capacity remained at 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 A g, respectively. -1 374, 356, 342, 336, 327, 320, 315, 311, and 296 mAh g at current densities -1 At an ultra-high 5.0A g -1 Under these conditions, the battery capacity retention exceeded 73%, demonstrating its superior redox kinetics and reversibility. Even more impressively, both discharge plateaus remained intact across all scan rates, such as... Figure 5b The corresponding GCD curve is shown below, from Figure 5b As can be seen, when the current density increases tenfold, only a slight plateau hysteresis is identified: the plateau at 3.42V is 0.14V, and the plateau at 2.91V is 0.16V. Another noteworthy advantage is the polarization voltage of the GCD, with a polarization voltage of 0.08V at the 2.91V plateau and 0.07V at the 3.42V plateau. Furthermore, this test example also evaluated the battery at 0.5A g... -1 Long-cycle performance at low current density, such as Figure 5c As shown, from Figure 5c As can be seen, after 500 cycles, only 15% capacity decay occurs, corresponding to a capacity decay rate of less than 0.03% per cycle. At 2.0A g -1 At the specified current density, 1300 long cycles only resulted in a 20% capacity loss, thus verifying the battery's cycle stability. Specifically, as shown below... Figure 5d As shown.

[0141] By analyzing 0.5A g -1 A simple mathematical analysis of the GCD curve under I can further clarify the reason why I 0 / I + The significant improvement in electrochemical performance is achieved through the presence of redox reactions. The MAI / / Cl-LDL / / Li battery at 0.5 A g... -1 The discharge curve at current density is as follows Figure 5e As shown, from Figure 5e As can be seen, taking the first inflection point of the 3.42V plateau as the boundary, the activation of the new conversion chemistry doubles the reversible capacity. Note that the capacity expansion at the 3.42V plateau is more significant because the traditional Ig... - / I3 - The 2.91V redox plateau corresponds to only two-thirds of the electron transfer per iodine (I) molecule. Therefore, the battery achieves a 138% increase in energy density, such as... Figure 5e The area covered by the vertical dashed lines is shown in the diagram. The diagram illustrates the enhancement of energy density in the voltage plateau region of the MAI / / Cl-LDL / / Li battery at different rate rates. Figure 5f As shown, from Figure 5f It can be seen from this that even at 4.5A g -1 At this level, the value remains around 102%. At 1.5A g -1 2.5A g -1 and 3.5A g -1 At the specified current densities, the energy density improvements were 132%, 111%, and 106%, respectively, significantly optimizing the actual power supply capability of the lithium-iodine battery. To demonstrate the superiority of this novel organic lithium-iodine battery, the MAI / / Cl-LDL / / Li battery, this test example also compared its electrochemical performance (e.g., discharge capacity, average voltage, and energy density) with other reported organometallic-iodine batteries (where the metals include lithium-ion, potassium-ion, sodium-ion, and magnesium-ion) and intercalated lithium-oxide batteries. The results are as follows: Figure 5g As shown, from Figure 5g As can be seen, the average output voltage, capacity, and energy density of the MAI / / Cl-LDL / / Li battery are superior to all reported metal-iodine batteries, including traditional organic lithium-iodine batteries and intercalated lithium-oxide batteries.

[0142] Test Example 5

[0143] Multiple experimental characterization methods, including UV-Vis spectroscopy, Raman spectroscopy, scanning electron microscopy, and energy dispersive spectroscopy, revealed the potential redox mechanism of two-electron transfer in novel organic lithium-iodine batteries. Specifically, a cold field emission scanning electron microscope (SU4800, Hitachi) was used to characterize the morphology and microstructure of the material; Raman spectroscopy was performed using a Renishaw 2000 microscope, and Raman spectra were collected using this instrument; and a Shimadzu UV-3600 spectrometer was used to collect UV-Vis absorption spectra.

[0144] Figure 6a The Raman spectra of the MAI cathode, i.e., the flexible cathode in Example 1, under different selected states of charge (SOC) are shown. Figure 6a As can be seen, under a fully discharged state of 2.0V, at 110cm -1 The strongest peak detected at point I is attributed to I - Ions, similar to the I in the original MAI material - Ions; as the charging process progresses to 3.0V, 167cm -1 A new main peak appears at 110cm. -1 The main peak at point I weakens significantly, corresponding to the decrease from I. - To I3 - The first conversion stage of the anion; in the fully charged state at 3.6V and 3.85V, the spectrum changed significantly, with the spectrum changing from 237 cm⁻¹ -1 and 328cm -1 The two newly appearing peaks at the point control the process, and these two peaks correspond to the stretching of the Cl-I bond in the second transition stage, indicating that the introduced chlorine (Cl...) - Ions stabilize the I generated at high potentials. + cation.

[0145] UV-vis absorption spectroscopy further supplements the above Raman results characterizing the iodine redox process. The UV-vis spectra of the MAI electrodes under different selected charge states are shown below. Figure 6b As shown. To avoid unexpected interference in subsequent processing, this test case directly measures the outer surface of the MAI electrode at different SOCs to collect all spectra. In... Figure 6b In the graphs shown, the evolution of the peak positions is still traceable. - The signal excited by ions at 2.0 V appears at 216 cm⁻¹. -1 Location, I3 - The signal excited by ions at 3.0 V appears at 270-290 cm⁻¹. -1 This clearly demonstrates that in the initial stage, I - / I3 -Redox transformation; when charged to a higher voltage, these characteristic peaks completely disappear, replaced by peaks appearing at 390-480 cm⁻¹. -1 The broad peak at this stage, because of I3 - Ions are continuously oxidized to I + Ions; furthermore, after two redox phases, this test case used SEM technology to visually observe the electrode surface. The results showed that the microstructure of the MAI electrode remained intact after cycling, retaining its original porous characteristics, and no regional detachment or cracking was observed. Figures 6c-6d As shown. At the same time, as Figures 6e-6f The EDX spectrum results shown confirm the coexistence of I and Cl elements.

[0146] Test Example 6

[0147] To gain a deeper understanding of the two-electron transfer reaction realized by the MAI / / Cl-LDL / / Li battery at the atomic scale, density functional theory (DFT) calculations were performed on the MAI / / Cl-LDL / / Li battery in this test case. All first-principles calculations in this test case were performed using the Vienna ab initio simulation package (VASP) using a plane-wave-based method (see: Kresse G, Furthmuller J. Efficientiterative schemes for ab initio total-energy calculations using a plane-wavebasis set. Physical Review B 1996, 54(16): 11169-11186. and Kresse G, Joubert D. From ultrasoft pseudopotentials to the projector augmented-wave method. Physical Review B 1999, 59(3): 1758-1775.). The exchange-correlation interaction is described by the generalized gradient approximation (GGA) in the Perdew-Burke-Ernzerhof (PBE) (see: Perdew P, Chevary A, Vosko H, Jackson A, Pederson R, Singh J, et al. Atmospheres, moleculars, solids, and surfaces-applications of the generalized gradient approximation for exchange and correlation. Physical Review B 1992, 46(11):6671-6687. and Perdew P, Wang Y. Accurate and simple analytic representation of the electron-gas correlation-energy. Physical Review B 1992, 45(23):13244-13249.), while the core valence electron interaction is calculated using the enhanced wave (PAW) pseudopotential. Furthermore, the vdW-D3 correction is invoked in all calculations to account for the dispersive interaction. Here, the supercell of MAI is 2×3×1.The plane wave basis set uses an energy cutoff of 500 eV, and the Brillouin zone uses a Monkhorst-Pack k-point grid with a 2×2×1 grid. These settings were configured in the calculations. The solid surface is constructed using a vacuum space. The convergence criteria for residual force and energy are set as follows: and 10 -6 eV (See: Li B, Wang C, Zhang Y, Wang Y. High CO2 absorption capacity of metal-based ionic liquids: A molecular dynamics study. Green EnregyEnvironment 2020. doi.org / 10.1016 / j.gee.2020.04.009.). To elucidate the mechanism of Cl-to-I ion conversion, this test case simulates several systems, including I3, ICl, and I2Cl, as detailed below. Figures 7a-7e As shown. In order to measure the stability of different systems, the cohesive energy (EC) is calculated from the DFT calculation according to the following formula (2).

[0148]

[0149] In formula (2), m and n are the number of I and Cl atoms; Esys, E I E Cl EC and Esub represent the energies of the system, isolated atom I, isolated atom Cl, and the MAI substrate, respectively. A higher EC value indicates a higher thermodynamic stability of the corresponding system.

[0150] The two-step reaction design starts from the initial I - Ions begin. Figure 7a The diagram shows the cohesive energy curves and redox products for different routes, with corresponding insets illustrating the optimized molecular structures of the redox products. The calculation results address two key issues: free Cl... - Is it beneficial to I? + What are the formation and stability of ions? And what are the most likely redox products? (No Cl-) - I3 - To I + The transformation is affected by a high energy barrier, resulting in I + Insufficient cohesive energy implies their thermodynamic instability. Studies have found that the introduction of Cl... - Significantly reduced from I3 - anion to I +The barrier to cation transformation. Furthermore, due to the high cohesive energy and low reaction energy barrier of I-Cl, the interhalogen redox products were identified as more favorable as I-Cl rather than I-Cl2, such as... Figure 7e As shown.

[0151] Furthermore, this test case analyzed the bond type and lone pair electron distribution of possible redox products using the associated electronic localization function (ELF). By definition, the ELF value ranges from 0 to 1, with an upper limit of 1 indicating complete electronic localization and a lower limit of 0 indicating complete electronic delocalization. Figure 7b As shown, the ELF model clarifies Cl - and I + Stable and robust electrical coupling between them can be detected in I-Cl, but not in I-Cl2. This finding also indicates that the redox products in I-Cl are more stable than those in I-Cl2. Furthermore, calculated atomic charges show that the charge states of I and Cl in I-Cl are opposite, indicating a strong interaction and significant electron transfer between them, such as... Figure 7c As shown, for I-Cl2, I and Cl have the same charge state, resulting in weak electron transfer. In summary, in Cl-containing electrolyte systems, I-Cl is the final dominant redox product, consistent with the aforementioned cohesive energy analysis. Therefore, the I-Cl bonds detected in Raman spectroscopy can be attributed to the I-Cl phase rather than the I-Cl2 phase.

[0152] Based on the above analysis, redox reactions based on a two-electron transfer mechanism have been clarified. For example... Figure 7d As shown, during charging, the original I - The ions are first oxidized to form I3. - (I 0 This corresponds to step 1 of the redox process; then, through the formation of I-Cl, Cl in the electrolyte... - Ions bind and stabilize positive I + ion.

[0153] Test Example 7

[0154] Under harsh low-temperature conditions, the slow kinetics and poor reversibility of batteries often lead to rapid capacity decay or even failure, thus limiting their application scenarios. Therefore, given the superior kinetics achieved by the novel conversion chemistry, this test case further evaluates the environmental adaptability of a novel conversion battery, namely the MAI / / Cl-LDL / / Li battery, over a wide temperature range of 25°C to -30°C. In this test case, electrochemical impedance spectroscopy (EIS) data were recorded using a CHI 760D multichannel electrochemical workstation. All capacity and energy densities were calculated based on the pure iodine content in the MAI cathode.

[0155] Figure 8aThe graph shows the discharge capacity of MAI / / Cl-LDL / / Li batteries in different temperature ranges. Figure 8a As can be seen, the battery operates stably within this range, with its discharge capacity decreasing as temperature decreases. Notably, at -30°C, the battery still supplies 51% of its room temperature capacity without any malfunctions or fluctuations. Specifically, the retention rate is 95% at 15°C, 91% at 5°C, 87% at -5°C, 80% at -15°C, and 67% at -25°C. Figure 8b The GCD curves of the battery at 25°C, -25°C, and -30°C are shown. Figure 8b As can be seen, all GCD curves contain two distinct pairs of charge / discharge plateaus. This clear electrochemical characteristic strongly supports the correlation with Ic. - / I + Two-stage redox chemical reactions involving redox reactions are not sensitive to temperature.

[0156] In addition, this test case further calculated the differential capacitance-voltage curve (dQ dV). -1 ), to elucidate dynamic evolution, such as Figure 8c As shown. As expected, the curves contain I3 at all temperatures. - / I 0 andI0 / I + Two pairs of fitted peaks corresponding to the two redox reactions. (And I3) - / I 0 In comparison, I 0 / I + The higher Y-axis values ​​for the redox pairs are due to their larger plateau region, consistent with the GCD results mentioned above. The decrease in potential polarization is mainly attributed to the weakened ion transport kinetics caused by the temperature sensitivity of the electrolyte.

[0157] EIS spectra of MAI / / Cl-LDL / / Li cells at different temperatures from 25℃ to -30℃ are as follows: Figure 8f As shown, the Rct, Ro values, and capacity retention data of MAI / / Cl-LDL / / Li batteries calculated at different temperatures from 25℃ to -30℃ are as follows: Figure 8g As shown, Figure 8f As shown in the EIS spectrum, the Rct (charge transfer resistance) value gradually increases with decreasing temperature, rising from approximately 22 Ω at 25 °C to 532 Ω at -30 °C, indicating that ion diffusion in the electrolyte is partially hindered. The capacity retention-temperature curve, however, shows the opposite trend. Figure 8gAs shown in the figure. In addition, this test case also underwent a long-cycle test at -25℃. The long-cycle performance results of the MAI / / Cl-LDL / / Li battery at -25℃ are shown in the figure below. Figure 8d As shown, the MAI / / Cl-LDL / / Li battery operates at -25°C and 1.0 A g. -1 The GCD curve under the condition of cycling is shown in the figure. Figure 8h As shown, from Figure 8d and Figure 8h As can be seen, the battery exhibits excellent long-term cycling characteristics at low temperatures, achieving up to 2,500 cycles at the cost of 20% capacity decay while maintaining a coulombic efficiency close to 100%.

[0158] Additionally, such as Figure 8e As shown, two MAI / / Cl-LDL / / Li cells connected in series can illuminate a large-sized (160mm×100mm) electroluminescent panel / cold light plate at a low temperature of -25℃.

[0159] In summary, addressing the shortcomings of traditional organic lithium-iodine batteries, such as low voltage and low capacity, this invention proposes an effective halogen inter-activation / reduction strategy. This strategy achieves stable and reversible redox reactions of multivalent iodine through electrolyte modification. The newly activated I... - / I + The redox mechanism brings about the desired two-electron transfer chemistry, greatly enhancing the electrochemical performance of organic lithium-iodine batteries, far exceeding that of traditional I-based batteries. - / I3 - / I 0 The corresponding electrochemical performance of similar batteries was compared. Specifically, in the novel organic lithium-iodine battery provided in the embodiments of the present invention, the triggered voltage plateau of 3.42V doubles the discharge capacity to 408mAh g. -1 More notably, this results in an energy density of 1324 Wh / kg. -1 The increase was to previously reported levels (typically 550-580 Wh / kg). -1 The additional energy contribution comes from the newly triggered high-voltage plateau region, significantly improving the battery's effective output capability. Furthermore, the novel redox reaction exhibits good kinetics and cycle stability. Experimental analysis and DFT simulations focused on resolving the Ig generated by the introduced chloride ions in the activation and stabilization high-voltage regions. + The important role played by cations reveals the Cl-containing - The specific mechanism of action of the additive is that it interacts with I-Cl via I-Cl. + Bonding effectively promotes I +The novel redox reaction exhibits excellent low-temperature adaptability, leading to the formation and stabilization of [the product / process]. Furthermore, it demonstrates a novel two-electron transfer iodine chemistry that significantly improves the output voltage, capacity, and other electrochemical performance parameters of organic lithium-iodine batteries, achieving unprecedented high energy density. The highly efficient interhalogen compound strategy developed in this invention holds promise for application in other halide conversion systems.

[0160] The above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any substitution of equivalent components or equivalent changes and modifications made within the scope of protection of this patent should still fall within the scope of this patent. Furthermore, the technical features, technical features and technical inventions, and technical inventions in this invention can be freely combined and used.

Claims

1. An organic lithium-iodine battery, characterized in that, The organic lithium-iodine battery includes: positive electrode; negative electrode; And organic electrolytes; The positive electrode active material used in the positive electrode includes iodide and / or bromide, and the organic electrolyte includes an organic solvent containing a chlorine-containing additive. The concentration range of the chlorine-containing additive is 0.01-0.1 M based on the total volume of the organic solvent, and the chlorine-containing additive is LiCl. Among them, the iodides used as positive electrode active materials include one or more of methylammonium iodide, trimethylammonium iodide, tetrabutylammonium iodide, and tetrabutylammonium triiodide, and the bromides used as positive electrode active materials include tetramethylammonium bromide and / or tetramethylammonium tribromide.

2. The organic lithium-iodine battery according to claim 1, characterized in that, The negative electrode includes lithium foil or graphite.

3. The organic lithium-iodine battery according to claim 1, characterized in that, The positive electrode comprises a current collector, a positive electrode active material, a conductive agent, and one or more binders.

4. The organic lithium-iodine battery according to claim 3, characterized in that, Based on the total weight of the positive electrode active material, conductive agent and binder as 100%, the amount of the positive electrode active material is 1-99 wt%, the amount of the conductive agent is 0.1-90 wt%, and the amount of the binder is 0.01-20 wt%, and the sum of the amounts of the positive electrode active material, conductive agent and binder is 100%.

5. The organic lithium-iodine battery according to claim 3 or 4, characterized in that, The current collector includes one of carbon cloth, carbon paper, aluminum foil, and nickel foam.

6. The organic lithium-iodine battery according to claim 1, characterized in that, The organic solvent containing chlorine-containing additives also contains lithium salt electrolytes.

7. The organic lithium-iodine battery according to claim 6, characterized in that, The concentration of the lithium salt electrolyte ranges from 0.01 to 10 M, based on the total volume of the organic solvent.

8. The organic lithium-iodine battery according to claim 6 or 7, characterized in that, The lithium salt electrolyte includes any one of LiTFSI, LiOTF, LiPF6, LiClO4, LiBF4, LiAsF6, LiCF3SO3, LiN(CF3SO2)2, LiBOB, LiDFOB, LiFSI, and LiNO3.

9. The organic lithium-iodine battery according to any one of claims 1-4 and 6-7, characterized in that, The organic solvent includes one or more of acetonitrile, dimethyl sulfoxide, tetrahydrofuran, propylene carbonate, methyl ethyl carbonate, ethylene carbonate, dimethyl carbonate, vinylene carbonate, propylene sulfite, methyl propionate, fluoroethylene carbonate, dimethoxyethane, and dioxolane.

10. A method for manufacturing an organic lithium-iodine battery according to any one of claims 1-9, characterized in that, include: The production of the positive electrode: The positive electrode active material, conductive agent, and binder are mixed evenly in a solvent to obtain a slurry. The slurry is then coated onto a current collector and dried to obtain the positive electrode. Assembly of organic lithium-iodine batteries: The positive electrode, negative electrode, and organic electrolyte are assembled to obtain an organic lithium-iodine battery.

11. The application of the organic lithium-iodine battery according to any one of claims 1-9 in automobiles, computers or robots.

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